Canister with pressure resistant sealing lid

Abstract

A canister including a canister body with a removable lid, incorporating a seal element of elastomeric material, releasably mountable to the canister body. The seal element, bonded to the lid, includes a first sealing surface engaging and sealing to the upper edge of the canister body, and a sealing bead spaced below the sealing surface and engaging and defining a seal with the inner surface of the canister body.

We claim: 
     
       1. A canister lid for removable engagement with a canister body and a sealing thereto along two spaced seal lines; said lid including a central portion and a peripheral edge portion about said central portion and in outwardly spaced relation thereto, said central portion and said peripheral edge portion being substantially rigid, and a softer annular elastomeric seal element bonded to and extending continuously about said central portion and solely adjacent said lid peripheral edge portion with a major portion of said central portion exposed within said annular seal element, said peripheral edge portion including a depending flange terminating in a lower edge, an inwardly directed locking bead integral and continuous with said depending flange adjacent said lower edge for a snap-locking engagement with a corresponding exterior locking bead on a canister body, said seal element including a downwardly directed face inward of said edge portion flange and above said lower edge of said edge portion flange, said seal element further including a depending flange inward of said downwardly directed face and depending therebelow in laterally spaced relation to said substantially rigid edge portion flange and said inwardly directed locking bead, said seal element flange having an outer face facing said edge portion flange and a free lower edge with an integral sealing bead immediately above the sealing element flange lower edge and laterally directed outward beyond said outer face and toward said edge portion flange. 
     
     
       2. A canister comprising a canister body with a body wall defining a canister interior and having an upper rim portion defining an upwardly opening mouth, and a lid releasably engageable with said rim portion in overlying relation to said mouth, cooperating locking means on said body and said lid releasably locking said lid to said body, said lid being substantially rigid, and a separate softer elastomeric seal element fixed to said lid, said seal element having vertically spaced upper and lower sealing components engaged with and sealed to said canister body at two vertically spaced positions completely about said mouth upon a locking of said lid to said body, said wall of said canister body having an outer surface, said locking means including a locking bead integral with said canister body wall and projecting outward from said outer surface peripherally thereabout adjacent said mouth, said canister body wall having a continuous smooth inner face for at least an upper portion of said wall at and below said mouth, said outer surface and said inner face being substantially parallel and defining a predetermined wall thickness therebetween, said canister wall having an upper edge extending between said outer surface and said inner face and of a width substantially equal to the wall thickness, said upper edge extending continuously about the canister, said lid including a central portion and a peripheral edge portion about said central portion in outwardly spaced relation thereto, said peripheral edge portion including an integral depending flange terminating in a lower edge, said locking means further including an inwardly directed locking bead integral and continuous with said depending flange adjacent said lower edge for a snap-locking engagement with said outwardly directed locking bead on the wall of said canister body, said elastomeric seal element being annular and fixed to and extending continuously about said central portion solely adjacent said lid peripheral edge portion with at least a manor area of said central portion exposed within said annular seal element and to a canister body interior defined by said body wall, said upper sealing component including a downwardly directed face inward of said edge portion flange and above said lower edge of said edge portion flange, said elastomeric seal element including a depending flange inward of said downwardly directed face and depending therebelow in laterally spaced relation to said lid edge portion flange, said seal element flange having an outer face facing said inner face of said canister body wall and an inner face facing toward and exposed to the canister interior, wherein said seal element flange is directly exposed to internal pressure within said canister interior, said lower sealing component comprising an integral sealing bead on said seal element flange, said sealing bead being laterally directed outward relative to said outer face of said seal element flange toward said lid edge portion flange, said upper and lower sealing components, upon locking engagement of said locking beads, being intimately compressed respectively against said canister upper edge and said canister inner face peripherally about said canister. 
     
     
       3. The canister of claim 2 wherein said upper and lower sealing components on said seal element, upon a locking of said locking beads of said lid and said body, define a pressure-accommodating space between said upper and lower sealing components for pressure-induced flexure of said elastomeric sealing element flange therein independent of said substantially rigid lid.